This invention relates to an apparatus for, and a method of, automatically latching to close and unlatching to open test sockets aligned on a burn-in board in order to load them with integrated circuits (ICs) to be tested or to undergo a burn-in process and also to remove these processed integrated circuits out of these sockets.
Packaged ICs are usually tested or sent in for a burn-in process by way of a socket (also called a test socket or a burn-in socket). Many such sockets are equipped with a lid or cover plate which serves the purpose of positioning and holding the ICs in place such that intimate contact is made between the IC leads and the contact pins on the socket. As shown in FIGS. 9 and 10, a socket of this type, generally indicated at 50, may have its lid 52 rotatably supported by its housing 54 around a support axis 56. A biasing spring (not shown) is provided such that the lid 52 will normally assume an open position shown in FIG. 9. In order to keep the lid 52 closed during a testing or burn-in process, a lever piece 58 is rotatably supported by the lid 52, a latch 60 being provided at one end of this lever piece 58 so as to be able to engage with a ledge 62 formed on the housing 54. Another biasing spring (not shown in FIG. 1) is provided so as to keep the lever piece 58 normally in the angular position with respect to the lid 52 as shown both in FIGS. 9 and 10. When the lid 52 is completely closed, this biasing spring serves to keep the latch 60 in the engaged position with respect to the ledge 62 as shown in FIG. 10. The lever piece 58 has two lugs 64 and 66 (herein referred to as the unlatching lug 64 and the latching lug 66, respectively) protruding in different directions from where it is axially supported by the lid 52. In FIGS. 9 and 10, numerals 68 indicate contact pins for contacting leads of the IC (not shown) to be loaded for a testing or burn-in process.
Typically, a large number of such sockets are arranged on a plate such as a burn-in board so that a large number of ICs can be tested or processed at the same time. It is both time-consuming and cumbersome to manually unlatch and open the lids of these many sockets prior to loading them with ICs and closing them by latching after they are loaded, or to open them by unlatching after a testing or burn-in process is completed and to close them again after the tested or processed ICs are removed from them.
It is therefore an object of the present invention to provide an apparatus for and method of automatically and efficiently latching to close and unlatching to open a large number of sockets of the type described above arranged on a plate such as a burn-in board.